*{
	margin: 0;
	padding: 0;
}
ul,ol{
	list-style: none;
}
button,input{
	outline: none;
	border: none;
}
a{
	text-decoration: none;
}
:root{
	font-size: 62.5%;
	width: 100vw;
	height: 100vh;
}
.container{
	/* 宽度绝对不能用vw来固定住它 */
	width: 1200px;
	margin: 0 auto;
}
.clearfloat::after{
	content: '';
	clear: both;
	display: block;
}